CN113702792B

CN113702792B - Display panel, light sensation detection method thereof and display device

Info

Publication number: CN113702792B
Application number: CN202110924710.3A
Authority: CN
Inventors: 卢峰
Original assignee: Shanghai Tianma Microelectronics Co Ltd
Current assignee: Shanghai Tianma Microelectronics Co Ltd
Priority date: 2021-08-12
Filing date: 2021-08-12
Publication date: 2023-04-28
Anticipated expiration: 2041-08-12
Also published as: US20230052815A1; US11562686B1; CN113702792A

Abstract

The invention discloses a display panel, a light sensation detection method thereof and a display device, and relates to the technical field of display, comprising the following steps: a plurality of light sensing detection units, the light sensing detection units including light sensing detection circuits; the light sensation detection circuit corresponding to the same light sensation detection unit comprises N light sensation detection branches connected in parallel, wherein N is more than or equal to 2; the N light sensation detection branches comprise a first light sensation detection branch and a second light sensation detection branch, the storage capacitor comprises a first storage capacitor positioned in the first light sensation detection branch and a second storage capacitor positioned in the second light sensation detection branch, and the capacitance value of the first storage capacitor is larger than that of the second storage capacitor. Therefore, at least two parallel light sensing detection branches are arranged in the same light sensing detection circuit, different light sensing detection branches correspond to different storage capacitors, the requirements of high sensitivity and multiple light intensity detection ranges are met, and the application range is wider.

Description

Display panel, light sensation detection method thereof and display device

Technical Field

The invention relates to the technical field of display, in particular to a display panel, a light sensation detection method thereof and a display device.

Background

From CRT (Cathode Ray Tube) age to liquid crystal age to the now coming OLED (Organic Light-Emitting Diode) age, the display industry has undergone decades of development to become more and more varied. The display industry is closely related to our lives, and the display technology is not available from the traditional mobile phones, flat-panel televisions, PCs, the current intelligent wearable devices, VR (virtual reality) and other electronic devices.

In order to meet the use demands of people, more and more functions can be realized by the electronic equipment. Electronic devices are typically provided with a light-sensitive detection unit, for example for optical fingerprint recognition or ambient light detection. In the current products, the sensitivity of the light sensing detection unit is fixed, and the light sensing detection unit can only be applied to scenes in a fixed light intensity environment, and has a relatively limited application range.

Disclosure of Invention

In view of this, the present invention provides a display panel, a light sensing detection method thereof, and a display device, wherein at least two light sensing detection branches are provided to meet the detection requirements under different light intensity environments, and the requirements of high sensitivity and multiple detection ranges are satisfied, so that the application range is wider.

In a first aspect, the present application provides a display panel, comprising: a plurality of light sensation detection units, the light sensation detection units including a light sensation detection circuit;

The light sensation detection circuit corresponding to the same light sensation detection unit comprises N light sensation detection branches connected in parallel, wherein the light sensation detection branches comprise storage capacitors, and N is more than or equal to 2; the N light sensation detection branches comprise a first light sensation detection branch and a second light sensation detection branch, the storage capacitor comprises a first storage capacitor positioned in the first light sensation detection branch and a second storage capacitor positioned in the second light sensation detection branch, and the capacitance value of the first storage capacitor is larger than that of the second storage capacitor.

In a second aspect, the present invention provides a light sensation detection method of a display panel, the display panel including: a plurality of light sensation detection units, the light sensation detection units including a light sensation detection circuit; the light sensation detection circuit corresponding to the same light sensation detection unit comprises N light sensation detection branches connected in parallel, wherein the light sensation detection branches comprise storage capacitors, and N is more than or equal to 2; the N light sensation detection branches comprise a first light sensation detection branch and a second light sensation detection branch, the storage capacitors comprise a first storage capacitor positioned in the first light sensation detection branch and a second storage capacitor positioned in the second light sensation detection branch, and the capacitance value of the first storage capacitor is larger than that of the second storage capacitor;

The light sensation detection method comprises the following steps:

and in the light sensation detection stage, selecting and conducting at least one of the first light sensation detection branch circuit and the second light sensation detection branch circuit, and utilizing at least one of the first light sensation detection branch circuit and the second light sensation detection branch circuit to carry out light sensation detection.

In a third aspect, the present application provides a display device, including a display panel, where the display panel is a display panel provided by the present invention.

Compared with the prior art, the display panel, the light sensation detection method and the display device provided by the invention have the advantages that at least the following beneficial effects are realized:

in the display panel, the light sensation detection method and the display device provided by the invention, at least two light sensation detection branches connected in parallel are included in the light sensation detection branch corresponding to the same light sensation detection unit, and different light sensation detection branches correspond to different storage capacitors. The smaller the capacitance value of the storage capacitor is, the higher the sensitivity of the light sensing detection unit is; the larger the capacitance value of the storage capacitor is, the larger the dynamic detection range is. Under the condition of weaker ambient light intensity, only the light sensing detection branch corresponding to the storage capacitor with smaller capacitance value can be conducted, for example, the second light sensing detection branch where the second storage capacitor is located is conducted, so that the light sensing detection unit has better sensitivity; under the condition of stronger ambient light intensity, the light sensation detection branch circuit where the storage capacitor with larger capacitance value is positioned can be conducted, for example, the first light sensation detection branch circuit where the first storage capacitor is positioned is conducted, so that the light sensation detection function under the condition of stronger ambient light is realized. Thus, under the condition of weaker ambient light, the high sensitivity requirement of the light sensing detection unit is ensured; under the stronger condition of ambient light, guaranteed light sense detecting element detection range demand, taken into account light sense detecting element's sensitivity and detection range demand, application range is wider, more is favorable to promoting user's use experience effect.

Of course, it is not necessary for any one product embodying the invention to achieve all of the technical effects described above at the same time.

Other features of the present invention and its advantages will become apparent from the following detailed description of exemplary embodiments of the invention, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is a schematic diagram of a light sensing circuit corresponding to a light sensing unit in the related art;

fig. 2 is a schematic plan view of a display panel according to an embodiment of the invention;

FIG. 3 is a schematic diagram of a light sensing circuit in a display panel according to an embodiment of the invention;

FIG. 4 is a schematic diagram of a light sensing circuit in a display panel according to an embodiment of the invention;

FIG. 5 is a schematic diagram of a light sensing circuit in a display panel according to an embodiment of the invention;

FIG. 6 is a timing diagram illustrating operation of the light sensing circuit of FIG. 5;

fig. 7 is another schematic diagram of a light sensing circuit in a display panel according to an embodiment of the invention;

FIG. 8 is a timing diagram illustrating operation of the light sensing circuit of FIG. 7;

FIG. 9 is a schematic diagram of a light sensing circuit in a display panel according to an embodiment of the invention;

fig. 10 is a diagram showing a structure of a film layer of a display panel according to an embodiment of the present invention;

FIG. 11 is a schematic diagram of another embodiment of a display panel according to the present invention;

FIG. 12 is a schematic diagram of another embodiment of a display panel according to the present invention;

FIG. 13 is a schematic diagram of another embodiment of a display panel according to the present invention;

FIG. 14 is a schematic diagram of another embodiment of a display panel according to the present invention;

FIG. 15 is a schematic diagram of a light sensing circuit in a display panel according to an embodiment of the invention;

FIG. 16 is a schematic diagram showing another embodiment of a light sensing circuit in a display panel according to the present invention;

FIG. 17 is a flowchart of a light sensation detection method according to an embodiment of the present invention;

fig. 18 is a top view of a display device according to an embodiment of the invention.

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise.

The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

Fig. 1 is a schematic circuit diagram of a light sensing circuit corresponding to a light sensing unit in the related art, where the light sensing circuit includes three transistors (respectively, a transistor Trst, a transistor Tsf, and a transistor Tsel), a photosensor D ' and a storage capacitor Cst, and further includes a reset scan line Rst, a fixed voltage signal line VDD ', a selection scan line Sel, and a voltage signal output line Vout '. Assuming that the light sensing detection circuit in fig. 1 is a fingerprint identification circuit, when fingerprint identification is performed, the fingerprint identification circuit includes a reset phase, an exposure phase and an electrical signal output phase:

In the reset stage, the transistor Trst is turned on in response to a control signal of the reset scanning line Rst to reset the fingerprint identification circuit; the reset voltage signal of the fixed voltage signal line VDD 'is transmitted to the gate of the transistor Tsf through the transistor Trst, and the voltage signal Vpixel of the gate of the transistor Tsf rises to the input voltage value of the first voltage signal line VDD', and at this time, the transistor Tsf is turned on;

in the exposure stage, when a finger contacts a screen, a light source reflects when irradiating on valley lines and ridge lines of the finger fingerprint, and as the reflection angles of the valley lines and the ridge lines and the reflected illumination intensities are different, light is projected onto a photoelectric sensor D ', so that the resistance value of the photoelectric sensor D' is changed, charges are generated, and photocurrent is formed; the voltage signal Vpixel of the gate of the transistor Tsf starts to drop due to the leakage current;

an electric signal output stage: because the reflection angles of the fingerprint valley lines and the fingerprint ridge lines and the reflected illumination intensities are different in the exposure stage, the generated photocurrents are different, so that the change values of the voltage signals Vpixel are different, fingerprint signals detected by the voltage signal output line Vout 'are also different, and the fingerprint identification function is realized by detecting the voltage signals of the voltage signal output line Vout'.

The sensitivity of the light sensing detection circuit is fixed, and the light sensing detection circuit can only be applied to scenes in a fixed light intensity environment and has a limited application range. The sensitivity of the light sensing detection circuit is expressed as a voltage difference DeltaV before and after illumination _Q Voltage difference DeltaV _Q Area S with photosensor _pin The specific relation is DeltaV _Q ＝S _pin /(S _pin +sigma), wherein sigma is an area equivalent influence quantity corresponding to stray capacitance, the area S of the photoelectric sensor _pin Much larger than sigma, so even with different photosensors, the voltage difference DeltaV before and after illumination _Q The ratio of the change of the light sensing circuit is basically kept unchanged, so that the sensitivity of the light sensing detection circuit is not improved by changing the photoelectric sensor. How to make the light sensing detection circuit have high sensitivity and multiple detection ranges is one of the technical problems to be solved in the current stage.

Therefore, the invention has the advantages that at least two light sensation detection branches are arranged, and different storage capacitors are arranged on different light sensation detection branches, so that the detection requirements under different light intensity environments are met, the requirements of high sensitivity and multiple detection ranges are met, and the application range is wider.

The following detailed description will proceed with reference being made to the drawings and detailed description of embodiments.

Fig. 2 is a schematic plan view of a display panel according to an embodiment of the present invention, fig. 3 is a schematic plan view of a light sensing circuit in the display panel according to an embodiment of the present invention, please refer to fig. 2 and 3, and a display panel 100 according to an embodiment of the present invention includes: a plurality of light-sensing detection units 20, the light-sensing detection units 20 including a light-sensing detection circuit 30;

The light sensing detection circuit 30 corresponding to the same light sensing detection unit 20 comprises N light sensing detection branches 10 connected in parallel, wherein the light sensing detection branches 10 comprise storage capacitors C, and N is more than or equal to 2; the N light sensation detection branches 10 include a first light sensation detection branch 11 and a second light sensation detection branch 12, and the storage capacitor C includes a first storage capacitor C1 located in the first light sensation detection branch 11 and a second storage capacitor C2 located in the second light sensation detection branch 12, where the capacitance value of the first storage capacitor C1 is greater than that of the second storage capacitor C2.

It should be noted that, fig. 2 illustrates the display panel 100 of the present invention by taking the display panel 100 of a rectangular structure as an example, and in other embodiments of the present invention, the display panel 100 may also be embodied as a rounded rectangle, a circle, an ellipse, or other special-shaped structures with arc edges, which is not particularly limited in the present invention. The display panel 100 shown in fig. 2 includes a display area AA and a non-display area NA, the light sensing units 20 are distributed in the display area AA, and in other embodiments of the present invention, the light sensing units 20 may be located in the non-display area NA, and the light sensing units 20 may be distributed only in a partial area in the display area AA, which is not limited in this particular aspect of the present invention. Fig. 2 also shows the light sensation detecting unit 20 only, and does not represent the actual shape or number.

Alternatively, the light sensing unit 20 in the display panel 100 may be used as a fingerprint recognition unit to implement a fingerprint recognition function of the display panel 100. In some other embodiments of the present invention, the light sensing unit 20 may also be used as an ambient light detection unit, implementing an ambient light detection function.

Specifically, each light sensing unit 20 in the display panel 100 corresponds to one light sensing circuit 30 as shown in fig. 3, each light sensing circuit 30 includes at least two light sensing branches 10 connected in parallel, and each light sensing branch 10 includes a storage capacitor C. In fig. 3, an example is illustrated in which one light sensing detection circuit 30 includes two light sensing detection branches 10, the two light sensing detection branches 10 are respectively represented by a first light sensing detection branch 11 and a second light sensing detection branch 12, the first light sensing detection branch 11 includes a first storage capacitor C1, and the second light sensing detection branch 12 includes a second storage capacitor C2, where a capacitance value of the first storage capacitor C1 is greater than a capacitance value of the second storage capacitor C2.

The sensitivity of the light sensing detection circuit 30 is expressed as a voltage difference Δv before and after illumination _Q Voltage difference DeltaV _Q And inversely related to the capacitance value of the storage capacitor C, the smaller the capacitance value of the storage capacitor C is, the higher the sensitivity of the light sensing detection unit 20 is; the larger the capacitance of the storage capacitor C, the greater the intensity of the detectable ambient light. Under the condition of weak ambient light intensity, only the light sensing detection branch circuit 10 corresponding to the storage capacitor C with a smaller capacitance value can be conducted, for example, the second light sensing detection branch circuit 12 where the second storage capacitor C2 is located is conducted, and the second light sensing detection branch circuit 12 is utilized to perform light sensing detection, so that the light sensing detection circuit 30 has better sensitivity. Under the condition of stronger ambient light intensity, the light sensation detection branch circuit 10 where the storage capacitor C with larger capacitance value is positioned can be conducted, for example, the first light sensation detection branch circuit 11 where the first storage capacitor C1 is positioned is conducted, and the light sensation detection is carried out by utilizing the first light sensation detection branch circuit 11, so that the light sensation detection function under the condition of stronger ambient light is realized. Thus, the storage capacitor C with smaller capacitance ensures the high sensitivity requirement of the light sensing detection unit 20 under the condition of weak ambient light; under the condition that the ambient light is strong, the storage capacitor C with a large capacitance value guarantees the detection range requirement of the light sensing detection unit 20, the high sensitivity and the multi-detection range requirement of the light sensing detection circuit 30 are considered, the application range is wider, and the use experience effect of a user is improved.

It should be noted that, when the same light sensing detection circuit 30 includes two light sensing detection branches 10, only one of the first light sensing detection branch 11 and the second light sensing detection branch 12 may be selectively turned on under different ambient light intensities, and the second light sensing detection branch 12 may be turned on only to be suitable for a stronger ambient light intensity environment, and the second light sensing detection branch 12 may be turned on only to be suitable for a weaker ambient light intensity environment, but the sensitivity is higher. Optionally, the first light sensing detecting branch 11 and the second light sensing detecting branch 12 may be turned on simultaneously, at this time, the overall sensitivity of the light sensing detecting circuit 30 is between the sensitivities when only the first light sensing detecting branch 11 and only the second light sensing detecting branch 12 are turned on, and the ambient light intensity that can be sensed is also between the ambient light intensities when only the first light sensing detecting branch 11 and only the second light sensing detecting branch 12 are turned on, so, although only two light sensing detecting branches 10 are introduced, the switching of three sensitivities and three ambient light intensities is realized, and the display panel has a wider application range.

In some other embodiments of the present invention, the number of light sensing branches 10 included in the same light sensing detection circuit 30 may be three or more, and the actual number of light sensing branches 10 included in the same light sensing detection circuit 30 may be determined according to actual needs, for example, refer to fig. 4, where fig. 4 is another schematic diagram of one light sensing detection circuit 30 in the display panel provided by the embodiment of the present invention, fig. 4 shows an embodiment in which the same light sensing detection circuit 30 includes three light sensing detection branches 10, and in addition to the first light sensing detection branch 11 and the second light sensing detection branch 12, a third light sensing detection branch 13 is further included, where the third light sensing detection branch 13 includes a third storage capacitor C3, and optionally, the capacitance value of the third storage capacitor C3 is larger than the capacitance value of the first storage capacitor C1, that is, in a plurality of light sensing detection branches 10 corresponding to the same light sensing detection circuit 30 needs to be ensured, the capacitance values of the storage capacitors C are different. Thus, by connecting a plurality of light sensation detection branches 10 in parallel, light sensation detection under the light intensity of more different environmental lights is realized, and the application range is wider.

In an alternative embodiment of the present invention, please continue to refer to fig. 3, the light sensing detection circuit 30 further includes a first node N1 and a second node N2, and in the same light sensing detection circuit 30, each light sensing detection branch 10 is connected in parallel between the first node N1 and the second node N2, and the first node N1 receives the first fixed voltage signal VCOM.

Specifically, referring to fig. 3, in the embodiment of the present invention, the light sensing detecting branch 10 is connected in parallel between the first node N1 and the second node N2, the potential of the first node N1 is constant, and when one or two light sensing detecting branches 10 are used for light sensing detection, light sensing signals can be transmitted to the second node N2 through the conducting light sensing detecting branch 10, so as to realize light sensing detection under different environmental light intensities.

In an alternative embodiment of the present invention, please refer to fig. 3 and 4, the light sensing detection branch 10 further includes a gating circuit S and a light sensing element D, respectively, the gating circuit S includes a control terminal 90, a first pole 91 and a second pole 92; in the same light sensing branch 10, the light sensing element D and the storage capacitor C are connected in parallel between the first node N1 and the first pole 91 of the gating circuit S, and the second pole 92 of the gating circuit S is connected to the second node N2; in the same light sensing circuit 30, the control terminals 90 of the gating circuits S of different light sensing branches 10 are connected to different gating signal terminals.

Specifically, taking fig. 4 as an example, the same light sensing detection circuit 30 includes three light sensing detection branches 10, and each light sensing detection branch 10 includes a light sensing element D connected in parallel with a storage capacitor C. Each light sensing branch 10 comprises a gating circuit S, specifically, the first light sensing branch 11 comprises a first gating circuit S1, the second light sensing branch 12 comprises a second gating circuit S2, and the third light sensing branch 13 comprises a third gating circuit S3; in the same light sensing detection circuit 30, the control ends 90 of different gating circuits S are connected to different gating signal ends, for example, the control end of the first gating circuit S1 is connected to the first gating signal end DM1, the control end of the second gating circuit S2 is connected to the second gating signal end DM2, the control end of the third gating circuit S3 is connected to the third gating signal end DM3, and the different gating circuits can be controlled by different gating signal ends, for example, only one of the light sensing detection branches 10 can be controlled to be turned on, and two or three light sensing detection branches 10 can be simultaneously controlled to be turned on, so that the turned-on light sensing detection branches 10 can perform light sensing detection under different environmental light intensities, and different sensitivity requirements can be realized.

In an alternative embodiment of the present invention, please refer to fig. 3, the gating circuit S includes a switching transistor, which includes a first switching transistor T1 located in the first light sensing branch 11 and a second switching transistor T2 located in the second light sensing branch 12, wherein the width-to-length ratio of the first switching transistor T1 is larger than the width-to-length ratio of the second switching transistor T2.

Specifically, with continued reference to fig. 3, in the first light sensing branch 11 and the second light sensing branch 12, the capacitance value of the first storage capacitor C1 is greater than that of the second storage capacitor C2, and the smaller the capacitance value of the storage capacitor C, the more easily the switch transistor off-state leakage current will affect. The width-to-length ratio of the first switching transistor T1 is larger than that of the second switching transistor T2, and the influence of off-state leakage of the second switching transistor T2 with smaller width-to-length ratio on the second storage capacitor C2 is reduced. Meanwhile, the smaller the capacitance value of the storage capacitor C, the faster the charge and discharge rate of the corresponding light sensing element D, and the invention sets the width-to-length ratio of the switch transistor in the light sensing detection branch circuit 10 with smaller capacitance value of the storage capacitor C, and simultaneously sets the width-to-length ratio of the switch transistor in the light sensing detection branch circuit 10 with larger capacitance value of the storage capacitor C, which is beneficial to balancing the charge and discharge rate of each light sensing element D in different light sensing detection branch circuits 10, so that the charge and discharge rates of different light sensing detection branch circuits 10 corresponding to the same light sensing detection circuit 30 are similar.

The invention introduces a separate switch transistor for each light sensing detection branch, and controls the conduction of the light sensing detection branch through the switch transistor. In the related art, a switch transistor is introduced between storage capacitors, whether the storage capacitors are connected in parallel is controlled by the switch transistor, and although different detection ranges can be realized by the switch transistor, the uncertainty of the overall parallel capacitance value after each switching is caused by the difference of the threshold value of the switch transistor and the capacitance of the switch transistor, and the calibration failure and other problems are easy to be caused. Therefore, in the scheme, a switch transistor is independently arranged for each light sensing detection branch, the light sensing element is directly connected with the storage circuit, no switch or transistor is arranged between the light sensing element and the storage circuit, the influence of the switch on light sensing detection is avoided, the uncertainty of the light sensing detection circuit is reduced, and the detection stability and the sensitivity stability of the light sensing detection branch are improved.

In an alternative embodiment of the present invention, fig. 5 is a schematic diagram of a light sensing detection circuit 30 in a display panel 100 according to an embodiment of the present invention, where the light sensing detection circuit 30 further includes a light sensing detection main circuit 40, and the light sensing detection main circuit 40 is connected to a second node N2;

the light sensing main circuit comprises a first transistor M1, a second transistor M2 and a third transistor M3, wherein a grid electrode of the first transistor M1 is connected with a first control signal end Reset, a first pole of the first transistor M1 and a grid electrode of the second transistor M2 are connected with a second node N2, a second pole of the first transistor M1 is connected with a first pole of the second transistor M2 and receives a second fixed voltage signal VDD, a second pole of the second transistor M2 is connected with a first pole of the third transistor M3, a second pole of the third transistor M3 serves as an output end Vout of the light sensing circuit 30, and a grid electrode of the third transistor M3 is connected with a second control signal end Read.

With continued reference to fig. 5, the light sensing detection circuit 30 provided in the embodiment of the present invention includes, in addition to at least two light sensing detection branches 10 connected in parallel, a light sensing detection main path 40, where the light sensing detection main path 40 is also connected to the second node N2, and thus, a signal of the light sensing detection branch 10 may be transmitted to the light sensing detection main path through the second node N2. Specifically, the light sensing main circuit 40 includes three transistors, namely a first transistor M1, a second transistor M2, and a third transistor M3, wherein the first pole of the first transistor M1 and the gate of the second transistor M2 are connected to the second node N2. In the Reset phase, the first transistor M1 is turned on in response to the control signal of the first control signal terminal Reset, the signal of the second fixed voltage signal terminal VDD is transmitted to the gate of the second transistor M2 through the first transistor M1, and the voltage of the second node N2 is raised to the voltage corresponding to the second fixed voltage signal terminal VDD, and at this time, the second transistor M2 is turned on. In the exposure stage, the finger contacts the screen, the light source reflects when irradiating the valley line and the ridge line of the finger fingerprint, the illumination intensity of the valley line and the ridge line is different, and the resistance value of the light sensing element D is changed when the light is projected onto the light sensing element D, so that charges are generated, and photocurrent is formed. The voltage at the second node N2 starts to drop due to the leakage current. Since the illumination intensities of the valley line and the ridge line of the fingerprint are different, the generated photocurrents are different, so that the variation values of the second node N2 are different, the fingerprint signals output by the output end Vout of the light sensation detection circuit 30 are also different, and the fingerprint identification function can be realized by detecting the voltage signals output by the output end Vout.

For the light sensing detection circuit 30 shown in fig. 5, in the practical application process, different light sensing detection branches 10 can be selectively turned on according to the ambient light intensity, and if the capacitance value of the third storage capacitor C3 is greater than the capacitance value of the first storage capacitor C1, and the capacitance value of the first storage capacitor C1 is greater than the capacitance value of the second storage capacitor C2, then the sensitivity of the second light sensing detection branch 12 corresponding to the second storage capacitor C2 is the highest, and the ambient light intensity that can be detected by the light sensing detection branch 10 corresponding to the third storage capacitor C3 is the largest. Fig. 6 shows a working timing diagram of the light sensing branch circuit 10 in fig. 5, which corresponds to three different environmental light intensities, respectively, the environmental light intensity in the t1 stage is the weakest, the environmental light intensity in the t2 stage is the stronger, and the environmental light intensity in the t3 stage is the strongest. In fig. 5 and fig. 6, in the stage t1, the switching transistor corresponding to the second light sensing branch 12 is turned on in response to the signal of the gating signal terminal DM2, and the second light sensing branch 12 performs light sensing detection, so that the corresponding sensitivity is the highest. In the stage t2, the switching transistor corresponding to the first light sensing branch 11 is turned on in response to the signal of the gating signal terminal DM1, and the first light sensing branch 11 performs light sensing. In the stage t3, the switching transistor corresponding to the third light sensing branch 13 is turned on in response to the signal of the gating signal terminal DM3, and the third light sensing branch 13 performs light sensing. In this way, different light sensation detection branches 10 are selected to perform light sensation detection under different environmental light intensities, the sensitivity of the circuit is guaranteed under weak light intensity, and light sensation detection under strong light intensity can be realized.

It should be noted that, the timing chart shown in fig. 6 only shows the situation that only one light sensing branch is turned on at the same stage, and in some other embodiments of the present invention, the number of light sensing branches turned on at the same stage may be set according to actual requirements, for example, two or more light sensing branches may be turned on at the same stage, so that the light sensing detection circuit has more light intensity detection ranges and sensitivity ranges.

Fig. 7 is another schematic diagram of the light sensing circuit 30 in the display panel according to the embodiment of the invention, please refer to fig. 7, in an alternative embodiment of the invention, the light sensing circuit 30 further includes a third node N3; the light sensing detecting branch 10 further includes a reset transistor (corresponding to transistors M4, M5, and M6), a driving transistor (corresponding to transistors M7, M8, and M9), and a light sensing element (corresponding to light sensing elements D1, D2, and D3), respectively, in the same light sensing detecting branch 10, the light sensing element D is connected in parallel with the storage capacitor C between the first node N1 and the first pole of the reset transistor; the first electrode of the reset transistor is also electrically connected with the gate electrode of the driving transistor, the first electrode of the driving transistor is connected with the second node N2, the second electrode of the driving transistor is connected with the third node N3, and the second node N2 receives a second fixed voltage signal VDD;

In the same light sensing circuit 30, the gates of the Reset transistors in the light sensing branches 10 are connected to the same first control signal terminal Reset, and the second poles of the Reset transistors in the light sensing branches 10 are connected to different Reset signal terminals (Vrst 1, vrst2, and Vrst3, respectively).

With continued reference to fig. 7, another possible configuration of the light sensing circuit 30 in the embodiment of the present invention is illustrated, in which the same light sensing circuit 30 includes three light sensing branches 10, and in other embodiments of the present invention, the number of light sensing branches 10 in the embodiment illustrated in fig. 7 may also be two or more, which is not particularly limited in the present invention. Each light sensing detection branch circuit 10 comprises a Reset transistor (M4, M5, M6), a driving transistor (M7, M8, M9), a light sensing element (D1, D2, D3) and a storage capacitor (C1, C2, C3), wherein the light sensing element D and the storage capacitor C are connected in parallel between a first node N1 and a first pole of the Reset transistor, a grid electrode of each Reset transistor is connected with the same first control signal terminal Reset, and in a Reset stage, the Reset transistors in each light sensing detection branch circuit 10 respectively receive control signals sent by the first control signal terminals; the second poles of the reset transistors in each light sensing branch circuit 10 are respectively connected with different reset signal terminals (Vrst 1, vrst2 and Vrst 3) for being conducted in response to signals of the reset signal terminals. Taking the first light sensing branch 11 as an example, after the first reset transistor M4 is turned on, the signal of the first reset signal terminal Vrst1 is transmitted to the gate of the first driving transistor M7 through the reset transistor M4, so that the first driving transistor M7 is turned on. In the exposure stage, when the light source irradiates on the valley line and the ridge line of the finger fingerprint, light is projected onto the first light sensing element D1 due to different reflection angles of the valley line and the ridge line and different reflected illumination intensities, so that the resistance value of the first light sensing element D1 is changed, charges are generated, and photocurrent is formed; due to the leakage current, the potential of the gate of the first driving transistor M7 decreases. Because the reflection angles of the fingerprint valley lines and the fingerprint ridge lines and the reflected illumination intensities are different in the exposure stage, the generated photocurrents are different, so that the voltage change value of the first driving transistor M7 output to the third node N3 is different, and the fingerprint identification function is realized.

Fig. 8 is a timing chart of an operation of the light sensing circuit 30 in fig. 7, which corresponds to three different environmental light intensities, respectively, the environmental light intensity in the t01 stage is the weakest, the environmental light intensity in the t02 stage is stronger, and the environmental light intensity in the t03 stage is the strongest. At the stage t01, the second reset signal terminal Vrst2 sends a high level signal to the second reset transistor M5, so that the second driving transistor M8 is turned on, and at this time, the second light sensing detection branch 12 is used for light sensing detection, and the second storage capacitor C2 in the second light sensing detection branch 12 has the minimum capacitance value, so that the sensitivity of the light sensing detection circuit 30 is the highest. In the stage t02, the first reset signal terminal Vrst1 sends a high-level signal to the first reset transistor M4, so that the first driving transistor M7 is turned on, and at this time, the first light sensing detection branch 11 is utilized to perform light sensing detection, and since the capacitance value of the first capacitor in the first light sensing detection branch 11 is greater than the capacitance value of the second capacitor in the second light sensing detection branch 12, the corresponding light intensity range is wider when the second light sensing detection branch 12 is adopted to perform detection. In the stage t03, the third reset signal terminal Vrst3 sends a high-level signal to the third reset transistor M6, so that the third driving transistor M9 is turned on, and at this time, the third light sensing detection branch 13 is used for light sensing detection, and since the capacitance value of the point storage capacitor C3 corresponding to the third light sensing detection branch 13 is the largest, the third light sensing detection branch 13 has a stronger light intensity detection range during detection, and the application range is wider. In this way, different light sensation detection branches 10 are selected to perform light sensation detection under different environmental light intensities, the sensitivity of the circuit is guaranteed under weak light intensity, and light sensation detection under strong light intensity can be realized.

It should be noted that, the timing chart shown in fig. 8 only shows the situation that only one light sensing branch is turned on at the same stage, and in some other embodiments of the present invention, the number of light sensing branches turned on at the same stage may be set according to actual requirements, for example, two or more light sensing branches may be turned on at the same stage, so that the light sensing detection circuit has more light intensity detection ranges and sensitivity ranges.

Fig. 9 is another schematic diagram of the light sensing circuit 30 in the display panel 0 according to the embodiment of the invention, referring to fig. 9, in an alternative embodiment of the invention, the light sensing circuit 30 further includes a light sensing main circuit 40, the light sensing main circuit 40 includes an output transistor M10, a gate of the output transistor M10 is connected to the second control signal terminal Read, a first pole is connected to the third node N3, and a second pole is used as the output terminal Vout of the light sensing circuit 30.

Specifically, with continued reference to fig. 9, the light sensing detection circuit 30 of the present invention further includes a light sensing detection main circuit 40, where the light sensing detection main circuit 40 is electrically connected to the third node N3, and when the output transistor M10 in the light sensing detection main circuit 40 is turned on, a light sensing detection signal can be transmitted to the output terminal of the light sensing detection circuit 30 through the third node N3 and the output transistor M10, so as to implement a light sensing detection function.

Fig. 10 is a diagram showing a film structure of a display panel 100 according to an embodiment of the present invention, in an alternative embodiment of the present invention, the display panel 100 includes a substrate 00, an array layer 01, and a light sensing element D, where the light sensing element D is located on a side of the array layer 01 away from the substrate 00 along a direction perpendicular to the substrate 00; the light sensing element D includes a first electrode E1 and a second electrode E2 disposed opposite to each other in a direction perpendicular to the substrate 00, the first electrode E1 being located on a side of the second electrode E2 facing the substrate 00; referring to fig. 3 and 10, the light sensing element D includes a first light sensing element D1 located in the first light sensing branch 11 and a second light sensing element D2 located in the second light sensing branch 12.

With continued reference to fig. 3 and 10, fig. 10 shows only one stacking relationship diagram of the light sensing elements D and the array layer 01 on the substrate 00 in the same light sensing detection circuit 30, and only the same light sensing detection circuit 30 including two light sensing elements D is illustrated as an example. The two light sensing elements D shown in fig. 10 are respectively located in different light sensing branches 10, the first electrode E1 of the first light sensing element D1 and the first electrode E1 of the second light sensing element D2 are respectively connected to different transistors, the second electrode E2 of the first light sensing element D1 and the second electrode E2 of the second light sensing element D2 are equipotential, for example, the second electrodes E2 of the different light sensing elements D may be connected together, or the second electrodes E2 of the different light sensing elements D share the same planar electrode. Alternatively, the structures and dimensions of the different light sensing elements D in the same light sensing circuit 30 may be identical to simplify the manufacturing process of the display panel 100.

Optionally, the light sensing element D in the embodiment of the present invention is a PIN photodiode, and a specific structure is that a low doped intrinsic semiconductor layer is added between a P-type semiconductor material layer and an N-type semiconductor material layer. The P-type semiconductor material layer can be used as the first electrode E1 of the light sensing element D in the invention, and the N-type semiconductor material layer can be used as the second electrode E2 of the light sensing element D in the invention; alternatively, the P-type semiconductor layer is used as the second electrode E2 of the light sensing element D in the present invention, and the N-type semiconductor material layer is used as the first electrode E1 of the light sensing element D in the present invention.

In an alternative embodiment of the present invention, with continued reference to fig. 3 and 10, in the same light sensing circuit 30, the distance between the first electrode E1 of the first light sensing element D1 and the array layer 01 is h1, and the distance between the first electrode E1 of the second light sensing element D2 and the array layer 01 is h2, where h1 < h2. Optionally, the array layer 01 is provided with a plurality of transistors, and the gate and the source and the drain of the transistors are both conductive structures. The smaller the distance between the light sensing element D and the array layer 01, the larger the voltage between the light sensing element D and the conductive structure in the array layer 01. Therefore, the distance h1 between the first electrode E1 of the first light sensing element D1 and the array layer 01 is set to be smaller than the distance h2 between the first electrode of the second light sensing element D2 and the array layer 01, so that the capacitance value of the corresponding first storage capacitor C1 in the first light sensing detection branch 11 is larger than the capacitance value of the corresponding second storage capacitor C2 in the second light sensing detection branch 12, and the first light sensing detection branch 11 has light sensing detection capability under larger environment light intensity, and meanwhile, the second light sensing detection branch 12 has better detection sensitivity.

It should be noted that fig. 3 and fig. 10 only show a scheme that the same light sensing detection circuit 30 includes two light sensing elements D located in two light sensing detection branches 10, and in other embodiments of the present invention, the same light sensing detection circuit 30 may further include three or more light sensing elements D, for example, please refer to fig. 4 and fig. 11, wherein fig. 11 shows another film structure diagram of the display panel provided by the embodiment of the present invention, a third light sensing element D3 is introduced into the light sensing detection circuit 30, and a distance h3 between a first electrode E1 corresponding to the third light sensing element D3 and an array layer 01 is smaller than a distance h1 between the first electrode E1 and the array layer 01 in the first light sensing element D1, so that a capacitance value of a storage capacitor C in the light sensing detection branch 10 where the third light sensing element D3 is located is the largest, and light sensing detection of the light sensing detection circuit 30 under a larger environment is realized, that is, and a wider detection range is provided.

Fig. 12 is a schematic diagram of another film structure of a display panel according to an embodiment of the present invention, in an alternative embodiment of the present invention, referring to fig. 3 and 12, in the same light sensing circuit 30, a first auxiliary metal layer M01 is disposed between at least a first electrode E1 of a first light sensing element D1 and an array layer 01 along a direction perpendicular to a substrate 00, and the first electrode E1 of the first light sensing element D1 overlaps the first auxiliary metal layer M01.

Specifically, fig. 12 shows a configuration in which the first auxiliary metal layer M01 is provided between the first electrode E1 of the first light-sensing element D1 and the array layer 01, and the auxiliary metal layer is not provided between the first electrode E1 of the second light-sensing element D2 and the array layer 01. When the first auxiliary metal layer M01 is introduced between the first electrode E1 of the first light sensing element D1 and the array layer 01, the first auxiliary metal layer M01 overlaps the first electrode E1 to form a capacitor, which increases the capacitance value of the first storage capacitor C1 in the first light sensing detection branch 11 where the first light sensing element D1 is located, so that the capacitance value of the first storage capacitor C1 is greater than the capacitance value of the second storage capacitor C2 in the second light sensing detection branch 12, thereby enabling the first light sensing detection branch 11 to have light sensing detection performance under larger environmental light intensity, and the second light sensing detection branch 12 to have higher detection sensitivity.

Fig. 13 is a schematic diagram of another film structure of a display panel 100 according to an embodiment of the present invention, in an alternative embodiment of the present invention, referring to fig. 2, 3 and 13, in the same light sensing unit 20, a second auxiliary metal layer M02 is disposed between a first electrode E1 of a second light sensing element D2 and an array layer 01 along a direction perpendicular to a substrate 00, and the first electrode E1 of the second light sensing element D2 overlaps the second auxiliary metal layer M02;

In the direction perpendicular to the substrate 00, the overlapping area of the first electrode E1 of the first light sensing element D1 and the first auxiliary metal layer M01 is S1, the overlapping area of the first electrode E1 of the second light sensing element D2 and the second auxiliary metal layer M02 is S2, S1 > S2.

Specifically, fig. 13 shows a configuration in which a first auxiliary metal layer M01 is provided between the first electrode E1 of the first light-sensing element D1 and the array layer 01, and a second auxiliary metal layer M02 is provided between the first electrode E1 of the second light-sensing element D2 and the array layer 01. The overlapping area S1 of the first auxiliary metal layer M01 and the first pole of the first light sensing element D1 is larger than the overlapping area S2 of the second auxiliary metal layer M02 and the first pole of the second light sensing element D2, the larger the overlap area, the larger the storage capacitance C will be, and therefore, the capacity value of the first storage capacitor C1 of the first light sensing detection branch 11 is larger than that of the second storage capacitor C2 of the second light sensing detection branch 12, so that the first light sensing detection branch 11 has light sensing detection performance under larger environment light intensity, and the second light sensing detection branch 12 has higher detection sensitivity.

Optionally, when the first auxiliary metal layer M01 and the second auxiliary metal layer M02 are simultaneously introduced, the first auxiliary metal layer M01 and the second auxiliary metal layer M02 are disposed in the same layer to simplify the manufacturing process of the display panel.

It should be noted that, in fig. 3 and fig. 13 only show the scheme that two light sensing elements D are included in the same light sensing detection circuit 30, in order to expand the detection range of the light sensing detection circuit 30, three or more light sensing elements D may be disposed in the light sensing detection circuit 30, for example, referring to fig. 4 and fig. 14, fig. 14 shows another film layer structure diagram of the display panel provided in the embodiment of the present invention, in addition to the first light sensing element D1 and the second light sensing element D2, a third light sensing element D3 is also introduced into the same light sensing detection circuit 30, and meanwhile, a third auxiliary metal layer M03 is introduced between the first pole of the third light sensing element D3 and the array layer 01, and a first auxiliary metal layer M01 is introduced between the first pole of the first light sensing element D1 and the array layer 01, and no auxiliary metal layer is introduced between the first pole of the second light sensing element D2 and the array layer 01. The overlapping area between the third auxiliary metal layer M03 and the first pole of the third light sensing element D3 is larger than the overlapping area between the first auxiliary metal layer M01 and the first pole of the first light sensing element D1, so that the capacitance value of the storage capacitor C in the light sensing detection branch 10 corresponding to the third light sensing element D3 is maximized, thereby further increasing the detection range of the light sensing detection circuit 30.

With continued reference to fig. 14, when the third auxiliary metal layer M03 and the first auxiliary metal layer M01 are simultaneously introduced, the third auxiliary metal layer M03 and the first auxiliary metal layer M01 may be disposed in the same layer to simplify the manufacturing process of the display panel.

It can be understood that, when three light sensing branches 10 are disposed in the same light sensing detection circuit 30, in order to distinguish the capacitance values of the storage capacitors C in the three light sensing detection branches 10, a scheme as shown in fig. 14 may be adopted, in which only the third auxiliary metal layer M03 corresponding to the third light sensing element D3 and the first auxiliary metal layer M01 corresponding to the first light sensing element D1 are introduced, and the second auxiliary metal layer M02 corresponding to the second light sensing element D2 is not introduced, which is beneficial to reducing the capacitance value of the second storage capacitor C2 in the second light sensing detection branch 12 where the second light sensing element D2 is located, thereby further improving the sensitivity of the second light sensing detection branch 12. Of course, in other embodiments of the present invention, in addition to the first auxiliary metal layer M01 and the third auxiliary metal layer M03, a second auxiliary metal layer corresponding to the second light sensing element D2 may be introduced, so long as different light sensing branches 10 in the same light sensing detection circuit 30 are guaranteed to have storage capacitors with different capacitance values, so as to achieve light sensing detection performance under different environmental light intensities.

In an alternative embodiment of the present invention, with continued reference to fig. 12 and 13, in the same light sensing unit 20, the distance between the first electrode E1 of the first light sensing element D1 and the array layer 01 is h1, and the distance between the first electrode E1 of the second light sensing element D2 and the array layer 01 is h2, where h1=h2.

Specifically, when the solution of introducing the auxiliary metal layer M0 between the first pole of at least part of the light sensing elements D and the array layer 01 is adopted to distinguish the capacitance values of the storage capacitors C of the different light sensing branches 10 in the same light sensing detection circuit 30, the different light sensing elements D in the same light sensing detection circuit 30 can be disposed at the same height, for example, the distances between the first light sensing element D1 and the second light sensing element D2 and the array layer 01 in the embodiments shown in fig. 12 and 13 are equal, and the film layer structure is beneficial to simplifying the manufacturing process of the display panel and improving the production efficiency of the display panel.

The embodiments shown in figures 10 and 11 illustrate schemes for distinguishing the capacitance values of different storage capacitances C in the same light sensing detection circuit 30 by varying the distance between the first pole of the light sensing element D and the array layer 01, the embodiments shown in fig. 12 to 14 illustrate schemes for distinguishing the capacitance values of different storage capacitances C in the same light sensing detection circuit 30 by introducing an auxiliary metal layer M0 between a first pole of a portion of the light sensing element D and the array layer 01. In addition to the two schemes, other schemes can be used to distinguish the capacitance of the storage capacitor C. For example, referring to fig. 15, fig. 15 is another schematic diagram of a light sensing detection circuit 30 in a display panel according to an embodiment of the invention, in an alternative embodiment of the invention, a first storage capacitor C1 includes m sub-capacitors C01, a second storage capacitor C2 includes n sub-capacitors C01, m > n, and m sub-capacitors C01 in the first storage capacitor C1 are connected in parallel, where m and n are positive integers.

Specifically, referring to fig. 15, an example is described where m=2, n=1, that is, the first storage capacitor C1 includes two sub-capacitors C01 connected in parallel, the second storage capacitor C2 includes one sub-capacitor C01, and when the two sub-capacitors C01 are connected in parallel in the first storage capacitor C1, the capacitance of the parallel capacitor corresponds to the capacitance of the first storage capacitor C1. When the two sub-capacitors C01 are connected in parallel, the capacitance value after the parallel connection is equal to the sum of the capacitance values of the two sub-capacitors C01, so that the capacitance value of the first storage capacitor C1 is larger than that of the second storage capacitor C2, the capacitance values of different storage capacitors C can be distinguished by adopting a mode of connecting the sub-capacitors C01 in parallel, and under the condition of stronger ambient light, the storage capacitor C with larger capacitance value ensures the detection range requirement of the light sensation detection circuit 30, considers the sensitivity and the detection range requirement of the light sensation detection circuit 30, has wider application range and is more beneficial to improving the use experience effect of users.

It should be noted that fig. 15 only shows a scheme in which the first storage capacitor C1 is formed by two sub-capacitors C01 connected in parallel, and the second storage capacitor C2 includes only one sub-capacitor C01, and when the second storage capacitor C2 includes only one sub-capacitor C01, it is beneficial to reduce the capacitance value of the second storage capacitor C2 and improve the sensitivity of the second light sensing detection circuit 30 where the second storage capacitor C2 is located. In other embodiments of the present invention, the number of sub-capacitors C01 included in each storage capacitor C can be flexibly set according to the actual situation, and the number of light sensing branches 10 included in the same light sensing circuit 30 can be flexibly set according to the actual situation. For example, when the same light sensing detection circuit 30 includes three light sensing detection branches 10, the number of sub-capacitors C01 included in different light sensing detection branches 10 may be respectively one, two, or three, and two sub-capacitors C01 are connected in parallel in the branch including two sub-capacitors C01; in the branch circuit comprising the three sub-capacitors C01, the three sub-capacitors C01 are connected in parallel, so that the scheme that the three light sensation detection branch circuits 10 correspond to three storage capacitors C with different capacitance values is realized.

In an alternative embodiment of the present invention, please refer to fig. 15, the capacitance values of the sub-capacitors C01 are equal, that is, the capacitance values of the sub-capacitors C01 included in each light sensing branch 10 are equal, so that when each sub-capacitor C01 is formed in the display panel, a related film structure is fabricated by adopting a uniform specification and dimension, which is beneficial to simplifying the fabrication process of the display panel and improving the production efficiency of the display panel.

In an alternative embodiment of the present invention, please continue to refer to fig. 15, the number of sub-capacitors C01 included in the second light sensing branch 12 is n, where n=1, or when n > 1, n sub-capacitors C01 in the second storage capacitor C2 are connected in series.

Specifically, when n=1, the number of the sub-capacitors C01 included in the second light sensing branch 12 is 1, which is beneficial to simplifying the manufacturing process of the second storage capacitor C2 in the second light sensing branch 12 and improving the sensitivity of the second light sensing branch 12.

In some other embodiments of the present invention, the number of sub-capacitors C01 included in the second light sensing branch 12 may be greater than 1, for example, please refer to fig. 16, fig. 16 shows another schematic diagram of a light sensing circuit 30 in a display panel 100 according to an embodiment of the present invention, which is only illustrated by taking the second light sensing branch 12 including two serially connected sub-capacitors C01 as an example, and in other embodiments of the present invention, the number of serially connected sub-capacitors C01 included in the second light sensing branch 12 may be 3 or more, which is not limited in particular. When the sub-capacitors C01 are connected in series, the capacitance value after the series connection is smaller than that of any one of the sub-capacitors C01. Therefore, the capacitance value of the second storage capacitor C2 is reduced by the serial connection of the sub-capacitors C01, which is favorable for realizing the differential design of the storage capacitors C corresponding to different light sensing branches 10 in the same light sensing detection circuit 30, and in addition, the detection sensitivity of the second light sensing branch 12 can be effectively improved.

It should be noted that, when the second storage capacitor C2 is formed by connecting at least two sub-capacitors C01 in series, the first storage capacitor C1 may include only one sub-capacitor C01, or may be formed by connecting two or more sub-capacitors C01 in parallel, so as to implement the differential design of the storage capacitors C in different light sensation detection branches 10.

In an alternative embodiment of the present invention, please refer to fig. 4, the number of light sensing branches 10 included in the same light sensing circuit 30 is N, where N is greater than or equal to 3, and the capacitance of the storage capacitor C included in different light sensing branches 10 in the same light sensing circuit 30 tends to increase.

Specifically, fig. 4 shows a scheme that the same light sensing detection circuit 30 includes three light sensing detection branches 10, the first light sensing detection branch 11 corresponds to the first storage capacitor C1, the second light sensing detection branch 12 corresponds to the second storage capacitor C2, and the third light sensing detection branch 13 corresponds to the third storage capacitor C3, where the capacitance value of the second storage capacitor C2 is smaller than that of the first storage capacitor C1, and the capacitance value of the first storage capacitor C1 is smaller than that of the third storage capacitor C3, so that the capacitance values of the second storage capacitor C2, the first storage capacitor C1 and the third storage capacitor C3 are presented with increasing trend, and thus, the light sensing detection branches 10 corresponding to the storage capacitors C with different capacitance values can perform light sensing detection under different environmental light intensity conditions, thereby meeting different detection requirements on different environmental light intensities, and being beneficial to expanding the detection range of the light sensing detection circuit 30.

In an alternative embodiment of the present invention, the capacitance of the storage capacitor C included in the different light sensing branches 10 varies with an equal difference or with a higher order equal difference. Specifically, when the capacitance values of the storage capacitors C included in the different light sensation detection branches 10 are equal to each other or are changed in higher order, the capacitance values of the storage capacitors C corresponding to the different light sensation detection branches 10 are presented with increasing trend, and meanwhile, the capacitance values of the different storage capacitors C are regularly and circularly used, and meanwhile, the light intensities under the corresponding detection environments of the different light sensation detection branches 10 have certain differences, so that the detection requirements under the environments of different light intensities are more met.

In an alternative embodiment of the present invention, the display panel 100 provided in the embodiment of the present invention further includes a light intensity detector electrically connected to the light sensing detection unit 20 for detecting the intensity of the ambient light. Specifically, a light intensity detector is disposed in the display panel, before light sensation detection is performed, the light intensity detector is used to detect the ambient light intensity, and the corresponding light sensation detection branch is selectively turned on according to the detected ambient light intensity, for example, when the ambient light intensity is weaker, the second light sensation detection branch 12 is selectively turned on to perform light sensation detection as shown in fig. 2; and when the ambient light intensity is strong, the first light sensing detection branch 11 can be selectively conducted to perform light sensing detection. The mode of the light sensing detection branch circuit 10 to be conducted is determined according to different environment light intensities, so that the pertinence is stronger, and meanwhile, the light sensing detection process is more flexible.

Based on the same inventive concept, the present invention further provides a light sensing method of the display panel 100, please refer to fig. 2 to 3, the display panel 100 includes: a plurality of light-sensing detection units 20, the light-sensing detection units 20 including a light-sensing detection circuit 30; the light sensing detection circuit 30 corresponding to the same light sensing detection unit 20 comprises N light sensing detection branches 10 connected in parallel, wherein the light sensing detection branches 10 comprise storage capacitors C, and N is more than or equal to 2; the N light sensation detection branches 10 comprise a first light sensation detection branch 11 and a second light sensation detection branch 12, the storage capacitor C comprises a first storage capacitor C1 positioned in the first light sensation detection branch 11 and a second storage capacitor C2 positioned in the second light sensation detection branch 12, and the capacitance value of the first storage capacitor C1 is larger than that of the second storage capacitor C2;

referring to fig. 17, the light sensation detection method includes:

in the light sensation detection stage, selecting and conducting at least one of the first light sensation detection branch circuit 11 and the second light sensation detection branch circuit 12, and utilizing at least one of the first light sensation detection branch circuit 11 and the second light sensation detection branch circuit 12 to carry out light sensation detection; fig. 17 is a flowchart of a light sensation detection method according to an embodiment of the present invention.

Specifically, since the light sensing detection circuit 30 provided in the present application includes at least two light sensing detection branches 10 connected in parallel, at least one light sensing detection branch 10 can be selectively turned on to perform light sensing detection according to different ambient light intensities during the light sensing detection stage. Under the condition of weak ambient light intensity, only the light sensing detection branch circuit 10 corresponding to the storage capacitor C with a smaller capacitance value can be conducted, for example, the second light sensing detection branch circuit 12 where the second storage capacitor C2 is located is conducted, and the light sensing detection is performed by using the second light sensing detection branch circuit 12, so that the light sensing detection unit 20 has better sensitivity. Under the condition of stronger ambient light intensity, the light sensation detection branch circuit 10 where the storage capacitor C with larger capacitance value is positioned can be conducted, for example, the first light sensation detection branch circuit 11 where the first storage capacitor C1 is positioned is conducted, and the light sensation detection is carried out by utilizing the first light sensation detection branch circuit 11, so that the light sensation detection function under the condition of stronger ambient light is realized. Thus, the storage capacitor C with smaller capacitance ensures the high sensitivity requirement of the light sensing detection circuit 30 under the condition of weak ambient light; under the condition that the ambient light is strong, the storage capacitor C with a large capacitance value guarantees the detection range requirement of the light sensing detection circuit 30, the sensitivity and the detection range requirement of the light sensing detection circuit 30 are considered, the application range is wider, and the use experience effect of a user is improved.

In an alternative embodiment of the invention, the display panel further comprises a light intensity detector, the light intensity detector is used for detecting the light intensity of the ambient light, and the light sensation detection branch needing to be conducted is selected according to the light intensity of the ambient light.

Specifically, before light sensing detection, the light intensity detector is used for detecting the ambient light intensity, and then the light sensing detection branch circuit to be conducted is selected according to the actual ambient light intensity, that is, which one or more light sensing detection branch circuits are specifically conducted is/are determined by the ambient light intensity detected by the light intensity detector, and the corresponding light sensing detection branch circuit is selected to be conducted according to the detected ambient light intensity, for example, when the ambient light intensity is weaker, the light sensing detection branch circuit with smaller capacitance value of the storage capacitor can be selected to conduct light sensing detection; and when the ambient light intensity is strong, the light sensation detection branch circuit with larger capacity value of the storage capacitor can be selected to conduct light sensation detection. The mode of the light sensing detection branch circuit which needs to be conducted is determined according to different environment light intensities, so that the pertinence is stronger, and meanwhile, the light sensing detection process is more flexible.

In an alternative embodiment of the present invention, please refer to fig. 3 and fig. 4, before the light sensing stage, the second light sensing branch 12 is turned on first, and the light sensing is performed by using the second light sensing branch 12;

Judging whether the output value of the light sensing detection circuit 30 is saturated or not, and if not, continuing to detect by using the second light sensing detection branch 12; if saturated, then: turning on the first light sensing detection branch 11, and performing light sensing detection by using the first light sensing detection branch 11; alternatively, the first light-sensing detection branch 11 and the second light-sensing detection branch 12 are turned on simultaneously, and light-sensing detection is performed by the first light-sensing detection branch 11 and the second light-sensing detection branch 12.

Specifically, this embodiment provides another scheme of selectively turning on the light sensing detection branch circuit 10, in any light intensity environment, the second light sensing detection branch circuit 12 with highest sensitivity and smallest storage capacitance value is turned on first, and whether other light sensing detection branch circuits 10 need to be switched is judged according to the output condition, specifically, whether the output value of the light sensing detection circuit 30 is saturated is judged, if not, the second light sensing detection branch circuit 12 is continuously used for detection; if the light detection is saturated, the first light detection branch 11 with larger capacitance value is selected for light detection, or the second light detection branch 12 and the first light detection branch 11 are selected for detection, and when the second light detection branch 12 and the first light detection branch 11 are selected, the sensitivity of the light detection circuit 30 is between the sensitivity when only the first light detection branch 11 is conducted or the sensitivity when only the second light detection branch 12 is conducted, and the sensed ambient light intensity is also between the ambient light intensity when only the first light detection branch 11 is conducted and the ambient light intensity when only the second light detection branch 12 is conducted, so that the function of automatically switching different light detection branches 10 under different ambient light intensities is realized, and the light detection under different ambient light intensities is realized.

Based on the same inventive concept, the present invention further provides a display device 200, and fig. 18 is a top view of the display device 200 according to the embodiment of the present invention, where the display device includes a display panel, and the display panel is the display panel 100 according to the embodiment of the present invention. In the display device 200, as the same light sensing detection circuit is provided with at least two light sensing detection branches connected in parallel, the storage capacitance values of the two light sensing detection branches are different, the sensitivity of the light sensing detection branch with smaller storage capacitance value is higher, and the light sensing detection circuit is suitable for light sensing detection in an environment with weaker light intensity; the light sensation detection branch with larger storage capacitance value has lower sensitivity, is suitable for light sensation detection under the environment with stronger light intensity, and meets the requirements of high sensitivity and wide detection range.

It should be noted that, in the embodiment of the display device 200 provided in the embodiment of the present application, reference may be made to the embodiment of the display panel 100 described above, and the repetition is omitted. The apparatus provided by the present application may be embodied as: any product or component with realistic functions such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like. The display device provided by the invention can be a liquid crystal display device, an organic light-emitting display device, a Mini-LED display device or a Micro-LED display device and the like.

According to the embodiment, the display panel, the light sensation detection method and the display device provided by the invention have the following beneficial effects:

While certain specific embodiments of the invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A display panel, comprising: a plurality of light sensation detection units, the light sensation detection units including a light sensation detection circuit;

the light sensation detection circuit corresponding to the same light sensation detection unit comprises N light sensation detection branches connected in parallel, wherein the light sensation detection branches comprise storage capacitors, and N is more than or equal to 2; the N light sensation detection branches comprise a first light sensation detection branch and a second light sensation detection branch, the storage capacitors comprise a first storage capacitor positioned in the first light sensation detection branch and a second storage capacitor positioned in the second light sensation detection branch, and the capacitance value of the first storage capacitor is larger than that of the second storage capacitor;

the light sensing detection circuit further comprises a first node and a second node, each light sensing detection branch is connected in parallel between the first node and the second node in the same light sensing detection circuit, and the first node receives a first fixed voltage signal;

The light sensing detection branch circuit further comprises a gating circuit and a light sensing element, wherein the gating circuit comprises a control end, a first pole and a second pole; in the same light sensing detection branch, the light sensing element and the storage capacitor are connected in parallel between the first node and a first pole of the gating circuit, and a second pole of the gating circuit is connected with the second node; in the same light sense detection circuit, the control ends of the gating circuits of different light sense detection branches are connected with different gating signal ends.

2. The display panel of claim 1, wherein the gating circuit comprises a switching transistor comprising a first switching transistor in the first light sensing branch and a second switching transistor in the second light sensing branch, wherein the aspect ratio of the first switching transistor is greater than the aspect ratio of the second switching transistor.

3. The display panel of claim 1, wherein the light detection circuit further comprises a light detection main path, the light detection main path being connected to the second node;

the light sensing detection main circuit comprises a first transistor, a second transistor and a third transistor, wherein a grid electrode of the first transistor is connected with a first control signal end, a first pole of the first transistor and a grid electrode of the second transistor are connected with the second node, a second pole of the first transistor is connected with a first pole of the second transistor and receives a second fixed voltage signal, a second pole of the second transistor is connected with a first pole of the third transistor, a second pole of the third transistor is used as an output end of the light sensing detection circuit, and a grid electrode of the third transistor is connected with a second control signal end.

4. The display panel of claim 1, wherein the light sensation detection circuit further comprises a third node; the light sensing detection branch circuit also comprises a reset transistor, a driving transistor and a light sensing element respectively, wherein in the same light sensing detection branch circuit, the light sensing element and the storage capacitor are connected in parallel between the first node and a first pole of the reset transistor; the first electrode of the reset transistor is also electrically connected with the gate of the driving transistor, the first electrode of the driving transistor is connected with the second node, and the second electrode of the driving transistor is connected with the third node, wherein the second node receives a second fixed voltage signal;

in the same light sensing detection circuit, a grid electrode of the reset transistor in each light sensing detection branch is connected with the same first control signal end, and a second electrode of the reset transistor in each light sensing detection branch is connected with different reset signal ends.

5. The display panel of claim 4, wherein the light sensing circuit further comprises a light sensing main circuit, the light sensing main circuit comprises an output transistor, a gate of the output transistor is connected to a second control signal terminal, a first electrode is connected to the third node, and a second electrode is used as an output terminal of the light sensing circuit.

6. The display panel according to claim 1, comprising a substrate, an array layer, and a light-sensing element, the light-sensing element being located on a side of the array layer away from the substrate in a direction perpendicular to the substrate; the light sensing element comprises a first electrode and a second electrode which are oppositely arranged along the direction vertical to a substrate, and the first electrode is positioned at one side of the second electrode facing the substrate; the light sensing elements comprise a first light sensing element positioned in the first light sensing detection branch and a second light sensing element positioned in the second light sensing detection branch.

7. The display panel according to claim 6, wherein in the same light sensing circuit, a distance between the first electrode of the first light sensing element and the array layer is h1, and a distance between the first electrode of the second light sensing element and the array layer is h2, wherein h1 < h2.

8. The display panel according to claim 6, wherein in the same light-sensing detection circuit, a first auxiliary metal layer is provided between at least the first electrode of the first light-sensing element and the array layer in a direction perpendicular to the substrate, and the first electrode of the first light-sensing element overlaps with the first auxiliary metal layer.

9. The display panel according to claim 8, wherein in the same light-sensing detection unit, a second auxiliary metal layer is provided between the first electrode of the second light-sensing element and the array layer in a direction perpendicular to the substrate, and the first electrode of the second light-sensing element overlaps with the second auxiliary metal layer;

and along the direction perpendicular to the substrate, the overlapping area of the first electrode of the first light sensing element and the first auxiliary metal layer is S1, and the overlapping area of the first electrode of the second light sensing element and the second auxiliary metal layer is S2, wherein S1 is more than S2.

10. The display panel according to claim 9, wherein in the same light sensing unit, a distance between the first electrode of the first light sensing element and the array layer is h1, and a distance between the first electrode of the second light sensing element and the array layer is h2, where h1=h2.

11. The display panel of claim 1, wherein the first storage capacitor comprises m sub-capacitors, the second storage capacitor comprises n sub-capacitors, m > n, the m sub-capacitors in the first storage capacitor are connected in parallel, and m and n are positive integers.

12. The display panel of claim 11, wherein the capacitance of each of the sub-capacitors is equal.

13. The display panel of claim 11, wherein n = 1, or n of the sub-capacitances in the second storage capacitance are connected in series when n > 1.

14. The display panel according to claim 1, wherein N is greater than or equal to 3, and in the same light sensing circuit, the capacitance values of storage capacitors included in different light sensing branches tend to increase.

15. The display panel according to claim 14, wherein the capacitance values of the storage capacitors included in different light sensing branches are changed in an equal difference or a higher order equal difference.

16. The display panel of claim 1, further comprising a light intensity detector electrically connected to the light sensing detection unit for detecting an intensity of ambient light.

17. A light sensation detection method of a display panel, the display panel comprising: a plurality of light sensation detection units, the light sensation detection units including a light sensation detection circuit; the light sensation detection circuit corresponding to the same light sensation detection unit comprises N light sensation detection branches connected in parallel, wherein the light sensation detection branches comprise storage capacitors, and N is more than or equal to 2; the N light sensation detection branches comprise a first light sensation detection branch and a second light sensation detection branch, the storage capacitors comprise a first storage capacitor positioned in the first light sensation detection branch and a second storage capacitor positioned in the second light sensation detection branch, and the capacitance value of the first storage capacitor is larger than that of the second storage capacitor;

The light sensation detection method comprises the following steps:

in a light sensation detection stage, selecting and conducting at least one of the first light sensation detection branch circuit and the second light sensation detection branch circuit, and utilizing at least one of the first light sensation detection branch circuit and the second light sensation detection branch circuit to carry out light sensation detection;

before the light sensation detection stage, the second light sensation detection branch is conducted firstly, and light sensation detection is carried out by using the second light sensation detection branch;

judging whether the output value of the light sensation detection circuit is saturated or not, and if the output value of the light sensation detection circuit is not saturated, continuing to detect by using the second light sensation detection branch; if saturated, then: the first light sensation detection branch is conducted, and light sensation detection is carried out by using the first light sensation detection branch; or, the first light sensation detection branch and the second light sensation detection branch are conducted at the same time, and light sensation detection is carried out by utilizing the first light sensation detection branch and the second light sensation detection branch.

18. The method of claim 17, wherein the display panel further comprises a light intensity detector, the light intensity detector is used to detect the intensity of the ambient light, and the light detection branch to be turned on is selected according to the intensity of the ambient light.

19. A display device comprising the display panel of any one of claims 1 to 16.